Blue, that is a rough situation, brother. You sound like you have a heart of gold, though - Stay strong.
Be careful in assuming someone is clean - There is plenty of stuff that doesn't show up on a screening. Keep your eyes open, so if they need help, you can get them help.
As for the behavior, here's what works for me - My wife gets to yell at me (never happens, I'm a gem
), we're equals. The kids? NEVER. If the kids act the fool, the usual response is they get a chance to get away from me until we can have an adult discussion.
If they choose the smart route and collect themselves. They know that if you bring nothing to the table, you leave with what you brought. If they need something, they need to come correct, with a plan. If you can do this, I'll do this or pay back this. etc. The equivalency doesn't matter much to me - the thought behind it does.
It is a little jerky at first, but through the years it slips into that social norm you have with good friends - You gladly have giving on either side, because there is mutual respect and trust. Give to live - First round is on me.
The payback is, a lot of doors open for them when they are generous (not just with money, but with time) and willing to show what they have to offer before extending their 'gimme' hand.
But bloody hell, it isn't easy. Had my heart ripped out a couple times. It grows back, tho
Hang in there, Blue